import java.lang.annotation.*;

@MyAnnotation(value = "abc", count = 9002, arrayParam = {"a", "b", "c"})  
@MyAnnotation("def")  
public class MyAnnotationMain {  
    public static void main(String[] args) {  
        System.out.println();  
  
        MyAnnotationRepeats a  = MyAnnotationMain.class.getAnnotation(MyAnnotationRepeats.class);  
        System.out.println(a);  
    }  
}

@Retention(RetentionPolicy.RUNTIME)  
@Target(ElementType.TYPE)  
@Repeatable(MyAnnotationRepeats.class)  
public @interface MyAnnotation {  
    String value();  
    int count() default 9001;  
    String[] arrayParam() default {};  
}

@Retention(RetentionPolicy.RUNTIME)  
@Target(ElementType.TYPE)  
public @interface MyAnnotationRepeats {  
    MyAnnotation[] value();  
}
 
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import java.io.PrintStream;  
import java.lang.reflect.Method;  
import java.lang.reflect.Parameter;  
  
public class Snippet {  
    public Snippet() {  
    }  
  
    public static void main(String[] args) {  
        Snippet s = new Snippet();  
        s.mySnippet(12, "Hello");  
    }  
  
    public void mySnippet(int param1, String param2) {  
        Object anonymObj = new Object() {};  
        Class<?> anonymClass = anonymObj.getClass().getEnclosingClass();  
        System.out.println(anonymClass.getName());  
        Method anonymMethod = anonymObj.getClass().getEnclosingMethod();  
        System.out.println("the name of this method is: " + anonymMethod.getName());  
        Parameter[] var6 = anonymMethod.getParameters();  
        int var7 = var6.length;  
  
        for(int var8 = 0; var8 < var7; ++var8) {  
            Parameter p = var6[var8];  
            PrintStream var10000 = System.out;  
            String var10001 = p.getName();  
            var10000.println("the parameter name ist" + var10001 + " : " + String.valueOf(p.getType()));  
        }  
  
    }  
}
 
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import java.lang.reflect.Field;  
import java.lang.reflect.Method;  
import java.lang.reflect.Parameter;  
  
public class MetaInformationSnippet {  
  
    public String exampleField = "helloWorld";  
    public static void main(String[] args) {  
        MetaInformationSnippet m = new MetaInformationSnippet();  
        m.interestingMethod("myInterestingValue", 0);  
    }  
  
    public void interestingMethod(String myInterestingParameter, int myOtherInterestingParameter) {  
  
        // This is the start of a snippet that could be copy-pasted into multiple different methods  
        Object anonymousObject = new Object() {};  
        Class<?> classOfThisMethod = anonymousObject.getClass().getEnclosingClass();  
        String genericString = classOfThisMethod.toGenericString();  
        System.out.println("genericString: " + genericString);  
        System.out.println();  
  
        Class<?> anonymClass =  anonymousObject.getClass().getEnclosingClass();  
        System.out.println(anonymClass.getName());  
        Method anonymMethod =  anonymousObject.getClass().getEnclosingMethod();  
        System.out.println("the name of this method is: " + anonymMethod.getName());  
        System.out.println();  
  
  
        // This creates an anonymous inner class, for which we can get the "outer" method. There are other methods: https://www.baeldung.com/java-name-of-executing-method  
        Method m = new Object() {}.getClass().getEnclosingMethod();  
        System.out.println("Method.name: " + m.getName());  
        for (Parameter p: m.getParameters()) {  
            System.out.println("Parameter.getName: " + p.getName());  
            System.out.println("Parameter.getType: " + p.getType());  
            System.out.println("Parameter.toString: " + p.toString());  
        }  
  
        System.out.println("Method.getReturnType: " + m.getReturnType());  
  
        for (Field f: classOfThisMethod.getFields()) {  
            System.out.println("Field.getName: " + f.getName());  
            System.out.println("Field.getType: " + f.getType());  
        }  
  
        // This is the end of this snippet  
  
    }  
}
 
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import java.lang.reflect.Method;  
import java.util.Random;  
import java.lang.annotation.ElementType;  
import java.lang.annotation.Retention;  
import java.lang.annotation.RetentionPolicy;  
import java.lang.annotation.Target;
  
public class CallMeMaybeMain {  
    static final Random r = new Random();  
    public static void main(String[] args) throws Exception {  
        maybeCallElements(ExampleClass.class);  
    }  
  
    public static void maybeCallElements(Class<?> c) throws Exception {  
        Object newInstance = c.getDeclaredConstructor().newInstance();  
        for (Method m: c.getMethods()) {  
            CallMeMaybe annotation = m.getAnnotation(CallMeMaybe.class);  
            if (annotation == null) {  
                // The annotation is not present on top of the method  
                continue;  
            }  
            if (true /**r.nextBoolean()**/) {  
                m.invoke(newInstance);  
            }  
              
        }  
    }  
}


public class ExampleClass {  
    @CallMeMaybe()  
    public static void methodA() {  
        System.out.println("Hello from Method A");  
    }  
  
    public void methodB() {  
        System.out.println("Hello from Method B");  
    }  
  
    @CallMeMaybe  
    public void methodC() {  
        System.out.println("Hello from Method C");  
    }  
}


@Retention(RetentionPolicy.RUNTIME)  
@Target(ElementType.METHOD)  
public @interface CallMeMaybe {  
}
 
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import lombok.*;  
  
@Setter  
@Getter  
@ToString  
public class Customer {  
  
    @NonNull  
    public String name;  
    public int id = nextId++;  
    private static int nextId;  
  
}
 
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import jdk.jfr.Name;  
import org.junit.jupiter.api.BeforeEach;  
import org.junit.jupiter.api.Test;  
  
import static org.junit.jupiter.api.Assertions.*;  
  
public class TestLombokAnnotations {  
  
    Customer c;  
  
    @BeforeEach  
    void initCustomer() {  
        c =new Customer();  
        c.id = 0;  
        c.name = "Testing Tester";  
    }  
    @Test  
    @Name("Check that Getters are generated correctly")  
    void testGetters() {  
  
        assertEquals(0, c.getId());  
        assertEquals("Testing Tester", c.getName());  
    }  
  
    @Test  
    @Name("Check that the toString generated by Lombok follows the same format")  
    void testToString() {  
        assertEquals("Customer(name=Testing Tester, id=0)", c.toString());  
    }  
  
    @Test  
    @Name("Check that the nextId++ pattern automatically generates the next id")  
    void testNextIdGeneration() {  
        Customer next = new Customer();  
        assertEquals(c.id + 1, next.id, "The next customer should have the id after the current customer");  
    }  
  
    @Test  
    @Name("Check that Lombok correctly thorws an Exception if you try to set a @NonNull Variable to null")  
    void testNonNullAnnotation() {  
        assertThrows(NullPointerException.class, () -> c.setName(null));  
    }  
}
 
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